Automation of the VATT

The most powerful spectrograph of the world - PEPSI - is also attached to the most powerful telescope in the world - the LBT. But there are times of course, where other instruments are used with the LBT, a time which does not have to be wasted. This brought up the idea to build a fiber link from the Vatican Advanced Technology Telescope (VATT) to PEPSI, allowing otherwise idle times to be used.


The VATT dome on Mt. Graham, building View on the 1.8m primary with adapter in the back


Light-collecting power of the VATT is of course limited compared to the LBT (light collecting area of the VATT main mirror is just 2.4% of the LBT's combined mirrors), and the fiber length of roughly 400m attenuates the light, more in the blue, even further, but for brighter stars, still enough light arrives at PEPSI.

Digging the new fiber train.

The adapter used for commissioning

the VATT at the test bench.

Transmission of VATT fiber vs. λ

In fall 2014, first light on PEPSI with the VATT was achieved.


Operating of PEPSI@VATT should be done in an automated, preferably robotic way. In Aug. 2014, it could be shown that acquisition and guiding (AG) using back-reflected light from a makeshift telescope adapter can be done in an automated way. The AG principle is similar enough to guiding the LBT, that a seamless integration of the VATT guiding system in the PEPSI control GUI could be realized ad-hoc.